1. Field of the Invention
The present invention relates generally to robotic gripper mechanisms, and more specifically to an improved actuator for the gripping action.
2. Background of the Invention
Typical robotic grippers (also known as end effectors) for automated data storage libraries are slow-speed pinching mechanisms for gripping onto a standard sized box-shaped media cassette. The size of the cassette usually dictates the range of movement of the gripper jaws. The simplest solution for proper movement of the jaws is to hinge them in the rear and provide an actuator to push them apart and pull them together in order to grip an object. Typically, a motor is used to drive a nut and linkage arrangement that moves the gripper finger together or apart.
Typical gripper mechanisms do not ramp up the motor to apply force to the jaws until the gripper makes contact with an object. Generally, the gripper has a limited time frame (e.g., 20 milliseconds) in which to grip the object. Because the motor must be ramped up to full speed after the object is encountered, part of the gripping time window must be used just to build up the requisite energy before the jaws can apply adequate force.
In addition to the time delay, the force produced by the motor must be generated from, a dead stop, thus limiting the amount of force that can be generated within the time window for a given sized motor.
Therefore, it would be desirable to have a method for increasing the speed and force of the gripping action with a given sized or perhaps smaller motor.